Sheet metal brake



W. G. MARSH Dec. 15, 1964 ETAL BRAKE m H M 3 w P k mi 6 R Q M B km 5 m United States Patent Ofiice 3,161,223 Patented Dec. 1 5, 1 964 This invention relates to a brake for forming sheet metal such as aluminum coil stock.

It has heretofore been suggested that a brake for bending and forming sheet metal such as aluminum coil stock may comprise a pair of members which are hinged to one another by a hinge such as a piano hinge having the leaves thereof fixed to the respective members. In the construction of such a brake in substantial length so that long lengths of sheet metal can be bent and formed, a major problem is that extreme difficulty is encountered in aligning the hinge leaves with respect to the longitudinal edges of the first and second members. This inaccuracy not only results in an improper bend but, in addition, mars the surface of the sheet metal where it is coated with an enamel or other coating.

It is an object of this invention to provide a novel brake for bending and forming sheet metal which obviates the foregoing disadvantages of prior art brakes.

It is a further object of the invention to provide such a brake which is light in weight, simple to operate and low in cost.

In the drawings:

FIG. 1 is a fragmentary perspective view of a brake embodying the invention.

FIG. 2 is a fragmentary plan view of a portion of the brake shown in FIG. 1.

FIG. 3 is a fragmentary end view of a portion of the brake shown in FIG- 1.

Referring to the drawings, the brake embodying the invention comprises a pair of channel shaped rails 10, 11 formed of aluminum extrusions and longitudinally spaced C shaped members 13 fixed on rails 10, 11. Each C shaped member 13 includes a lower arm 14 which is fixed by screws to the rails 10, 11 and an upper arm 15 that overlies the lower arm 14 in spaced relation thereto.

A first member 16 in the form of a channel shaped aluminum extrusion is fixed on the lower leg 14 and a second channel shaped aluminum extrusion 17 is hinged thereto in accordance with the invention.

As shown in FIG. 2, channel shaped members 16, 17 are formed with mating integral projections 18, 19 along their longitudinal edges that are made by machining the edges along fiat transverse planes. In addition, the projections are provided with openings 20, 21 that are formed during the extrusion process and are aligned when the projections 18, 1? are intermeshed. A pin 22 extends through the openings to complete the hinge. In this manner, swingable member 17 is hinged to member 16 along an accurate axis.

An anvil plate or member 23 is provided in overlying relation to the base 24 of member 16 to clamp a piece of sheet metal S against the fiat surface 24a in clamping relation, as shown in FIG. 3. Anvil member 23 includes a sharp edge 25 adjacent the sheet metal S and a tapered surface 2d tapering away from the edge 25.

Means are provided for selectively clamping the anvil member 23 in position and comprises a backing plate 27 having inclined earns 28 thereon in underlying relation to the upper arm 15. Plate 27 is loosely mounted over the anvil member and is adapted to be moved longitudinally of the anvil member by a lever 29 that is pivoted to a block 30 on the plate 27. The lower end of the lever 29 is connected by link 31 to the lower arm 14. Spring plates 32 are fixed to the upper arm 15 and extend between brackets 33 fixed on the anvil member 23 to tend to elevate the backing plate when the cam block 28 is moved to the right as viewed in FIG. 1 to relieve the clamping pressure on anvil member 23.

When a piece of sheet metal is to be bent, the lever 29 is swung to relieve the clamping pressure and elevate the backing plate 27. The sheet metal is inserted in proper position between member 16 and anvil member 23 and the lever 29 is actuated to clamp the sheet metal.

- Handles 35 on the second member 17 are then used to swing the second member 17 upwardly and bend the sheet metal to the desired angle (FIG. 3).

By eliminating any separate hinge which is fastened to the members and providing the integral hinge construction, an accurate bend is applied to the sheet metal without marring the surface of any coating on the sheet metal.

I claim:

1. In a brake for bending sheet metal, the combination comprising a first member having a clamping surface,

means for clamping a piece of metal on said clamping surface of said first member,

a second member having a bending surface,

each of said first and second members having substantially the entire length of the longitudinal edges thereof formed with longitudinally spaced intermeshing integral projections,

each said projection of each said member being positioned such that all portions thereof do not extend above the plane of the surface of its corresponding member when the surfaces are substantially aligned,

said projections having aligned openings therein,

a hinge pin extending through said integral projections and thereby defining a hinge so that said second member may be swung relative to the first member for bending sheet metal about said anvil member.

2. The combination set forth in claim 1 wherein each said projection includes flat transverse surfaces on the ends thereof.

3. The combination set forth in claim 1 wherein each said member is generally channel shaped in cross section.

4. In a brake for bending sheet metal, the combination comprising a pair of spaced base rails,

a plurality of C shaped members positioned on said base rails at longitudinally spaced points,

each said O shaped member comprising a lower arm fixed to said rails and an upper arm spaced from and overlying said lower arm,

a first member fixed on the lower arms of said C shaped members and having a clamping surface,

an anvil member, 1

means for locking said anvil member on said first member to clamp a piece of sheet metal between said anvil member and said clamping surface of said first member,

a second member having a bending surface,

said first and second members having longitudinally spaced integral intermeshing projections extending outwardly along substantially the entire length of the longitudinal edges thereof,

each said projection of each said member being positioned such that all portions thereof do not extend above the plane of the surface of its corresponding member when the surfaces are substantially aligned,

said projections having aligned openings,

a hinge pin extending through said openings to define a hinge,

said anvil member having a longitudinal edge extending along said hinge line,

said means for clamping said anvil member against said first member including cam means between said upper arms of said 6 shaped members and said anvil member.

5. In a brake for bending sheet metal, the combination 7 comprising a first metal extrusion 'member having a clamping surface, means for clamping'a piece of nietal'against said clamp-v ing surface of said first member, r a second inetal extrusion member having surface, i I each of said first and secondmember having. substantially the entire length of the longitudinal edges formed with intermeshing integral projections,

a bending each said projection of each saidt member being positioned such that all portionsthereo'f dornot extend above the plane of the surface of itscorresponding v member when the surfaces'are substantially aligned, said projections having aligned extruded openings therein, a hinge pin extending-through said integral projections and thereby defining a hinge to swing the second,

member relative to the first member :for I bending about said anvil member. t a 6. In a brake for 'bendingsheet metal, the combination comprising i 1 V j I a pair of spaced extruded metal base rails, I a plurality of -C shaped members positioned on said base rails at longitudinally spaced points, I

each said 0 shaped member comprising a lower arm I fixed tosaid rails and an upper arm spacedrfrorn and overlying said lower arm, a a a a first extruded metal member fixed on the lower arms face, an extruded metal anvil member, means for locking said anvil member, on said first memher to clamp a piece of sheet metalxbetween said 36' of said C shaped members and having a clamping suranvil member and said clamping surface of said first member,

: 'a second extruded metal memberihaving a bending sur-s;

face, a I 1 said first and second members having longitudinally spaced integral intermeshing projections extending outwardly along substantially the entire length of the longitudinal edges, 5

each said projection of each said member being posi- V tioned such that all portions thereof do not extend above the planeof the surface of its corresponding member when the surfaces are substantially aligned, said projections having aligned openings, a hinge pin extending through said openings to define a g r said anvil member having a longitudinal edge extending along said hinge line, said means for clamping said anvil member against said first member including Cami means betweenvsaid upper arms of said 0 shaped members and said anvil member. I r 7. In a brake for bending sheet metal, the combination comprising a first member having a flat clamping surface,-

' an anvil member for clamping a piece of metal against said flat clamping surface onsaid first member,

' a second member having a fiat/bending surface,

each of said first and second members having substan-' tially the entire length of the longitudinal edges thereof formed with longitudinally spaced intermeshing integral projections,

- eachsaidprojection of each said member having a surface thereof lying in the plane of the flat surface of its corresponding member, I V i said projections having aligned openings therein, and'a hinge pin extendingthrough' said integral projecs tions andthereby defining a hinge so that said second member may be swung relative to said first member to bend said metal about said-anvil member.

References Cited by the Examiner t UNITED STATES PATENTS 134,376=12/72 Gorton.

10/88 Fitzberger 153l6 6/ 12 Wells 153--16 8/54 'Smith' 153-16 FOREIGNBATENTS Y 9 /17 Germany. 7 10/32 Sweden. 7

LANHAM, Primary Examiner. iggins r rfsriarngnsoN, Examiner, 

1. IN A BRAKE FOR BENDING SHEET METAL, THE COMBINATION COMPRISING A FIRST MEMBER HAVING A CLAMPING SURFACE, MEANS FOR CLAMPING A PIECE OF METAL ON SAID CLAMPING SURFACE OF SAID FIRST MEMBER, A SECOND MEMBER HAVING A BENDING SURFACE, EACH OF SAID FIRST AND SECOND MEMBERS HAVING SUBSTANTIALLY THE ENTIRE LENGTH OF THE LONGITUDINAL EDGES THEREOF FORMED WITH LONGITUDINALLY SPACED INTERMESHING INTEGRAL PROJECTIONS, EACH SAID PROJECTION OF EACH SAID MEMBER BEING POSITIONED SUCH THAT ALL PORTIONS THEREOF DO NOT EXTEND ABOVE THE PLANE OF THE SURFACE OF ITS CORRESPONDING MEMBER WHEN THE SURFACES ARE SUBSTANTIALLY ALIGNED, SAID PROJECTIONS HAVING ALIGNED OPENINGS THEREIN, A HINGE PIN EXTENDING THROUGH SAID INTEGRAL PROJECTIONS AND THEREBY DEFINING A HINGE SO THAT SAID SECOND MEMBER MAY BE SWUNG RELATIVE TO THE FIRST MEMBER FOR BENDING SHEET METAL ABOUT SAID ANVIL MEMBER. 